ALL

3. 1. More in number
2. Respond rapidly to chemokines
3. Attach more firmly to the adhesion molecules
4. Short lived
5. Apoptosis and disappear with in 24 to 48 hours

5. ACUTE LYMPHOBLASTIC
LEUKEMIA
DR.T.ARIVAZHAGAN
Department of Pathology

7. Definition
Acute lymphoblastic leukaemia is
malignant disease of marrow in which
early lymphoid precursors proliferate
and replace the normal
haematopoietic cells.

8. Lymphoblast Myeloblast
Smaller Larger
Scanty cytoplasm Moderate
Auer rod absent May be present
Coarse nuclear chromatin Fine
Indistinct nucleoli Prominent nucleoli
Myeloperoxidase negative Positive
Sudan black B negative Positive
PAS stain positive Negative

10. Introduction
1. Commonest form of malignancy in
childhood.
2. Peak incidence 4-5 Years of age.
3. 85% are B cell
4. 15%are T cell

12. PREDISPOSING FACTORS
1. Genetic
2. Down’s, Turner, Klienfelter
3. PNH
4. Ataxia telangiectasia
5. Environmental
6. Ionising radiation
7. Drugs
8. Alkylating agents
9. Benzene exposure

14. FAB CLASSIFICATION
1. ALL L1 - CHILDREN
2. ALL L2 - M.C TYPE ADULTS
3. ALL L3

16. S.NO MORPHO.LOGY L1 L2 L3
1
SIZE
SMALL
LARGE
HETEROGENOUS
LARGE
HOMOGENOUS
2 CYTOPLASM SCANTY MODERATE
MODERATE,INTENS
ELY BASOPHILIC
3 N/C RATIO HIGH LOWER LOWER
3
CYTOPLASMIC
VACUOLES
+/- +/- PROMINENT
4
NUCLEAR
MAMBRANE
REGULAR
IRREGULAR
WITH CLEFTING
REGULAR
5 NUCLEOLI INDISTINCT PROMINENT 1-2 PROMINENT 1-2

20. INVESTIGATIONS
• CBC-Anaemia, Thrombocytopenia,
Leucopenia or leucocytosis
• PS- Circulating blast seen
• BONE MARROW- At least 30% blast (FAB)
• 20% blast(WHO)
• MPO Negative